Dynamo-electric machine



Feb. 6, 1923. 1,444,458 v. H. GRElssER DYNAMO ELECTRIC MACHINE Filed Oct. 2l, 1931 Invemtmvv Victoxfq H. Graisses?? Patented Feb. 6, 1923.

UNITED' STATES PATENT OFFICE.

VICTOR H. GBEISSER, OF SPOKANE, WASHINGTON, ASSIGNOR TO GENERAL ELECTRIC COMPANY, A CORPORATION OF NEW YORK.

DYNAMO-ELECTRIC MACHINE.

Application filed October 21, 1921. Serial No. 509,324.

ol! iff/'mm if may concern:

Be it known that I, Vieron ll. (ina-Isaak. a citizen ot' the l'fnited States. residing at Spokane. in the county of Spokane, State ot' ll'ashington. have invented certain new and iiset'ul improvements in Dynamo-Electric Machines, oi* which the following is a specihcation.

My invention relates to dynamo electric machines and has tor its object an etiicient arrangement tor Ventilating such machines.

As is well known. the relatively rotating members ot dynamo electric machines are provided with radially extending Ventilating spaces or ducts through which air is forced for cooling the members ot the 1nachine. The entrance or inlet to such ducts. as heretofore constructed. is at right angles to the flow ot air in the air gap between the relatively rotating members. thus producing eddies and reverse flow ot air in the air ducts. which materially reduces the amount of air entering the Ventilating spaces` the effect of these eddies and reverse iiow ot air being considerably increased with the increase of speed ot' rotation of the revolving member. In accordance with my invention, in order toA secure the maximum flow of air into the Ventilating spaces at right angles to the flow of air in the air gap, I provide a gradual change of shape ot' the entrance or inlet to the Ventilating space by l new and novel shaping of the slot closing wedges.

For a better understanding ot my invention. reference may he had to the. following description taken in connection with the accompanying drawing. in which Fig. 1 is a sectional View ot' a portion of a dynamo electric machine embodying my invention; Fig. 2 is an enlarged view ot a portion ot' Fig. 1: and Fig. 3 is a View similar to Fig. 2 showing a modification of my invention.

In the drawing. I have shown my invention embodied in an alternating current dynamo electric machine having a stationary member 1 and a rotatable member 2. The stationary member is provided with usual slots 3 which contain windings 4. The member 1 is provided with Ventilating spaces or ducts 5 through which cooling air is forced for Ventilating the core and windings of the stationary member. The slots 3 have wedges 6 in the top thereof, which act .as coil retaining devices. In accordance with my invention7 eac-h of these wedges has its external surface T in the ventilating space extendin' Substantially across the width ot' the slot and angularly disposed with reference to the periphery S ot the stationary member, whereby the wedges have a substantially triangular cross section in the Ventilating space. The

' inclination of the surface T is such that the narrow part oi the triangle extends in the direction ot' rotation ot tie rotatable member, that is` the trailing tip 9 ot' the wedge is cut away in the Ventilating space. The surface T extends substantially across the width of the slot. The movement of the air in the air gap due to the rotation of the rotatable member is at right angles to the Ventilating spaces 5, but by shaping the wedges as described above. the shape ot the inlet to the ventilating spaces is gradually changed and the air in entering therein will not have to make a right angle turn. thus reducing eddies and improving thecirculation ot' air through the Ventilating spaces.

In order not to obstruct the entrance of air into the Ventilating space. I also prefer to cut away the wedge at the leading tip so as to have a surface i() in the Ventilating space extending substantially in line with the side ot' the slot.

The stationary member 1 is of the usual laminated construction with space blocks 1l for forming the Ventilating spaces 5. In large machines` a number of Ventilating spaces are provided in the core structure. The rotatable member 2 is shown as having definite poles 12. but it is understood that my invention is applicable to machines in which both members have distributed windings like stationary member l.

In the construction shown in Fig. 3, the wedge has a curved surface 7 cut away at the trailing tip 9 instead of being a flat surface as shown on Figs. 1 and By thus shaping the surface 7', a more gradual change of shape of the inlet to the ventilating duct is obtained. In Fig. 3 also, the-space blocks 11 have their tips 13 curved away from the direction of rotation of the rotatable member and thereb still further improve the circulation of airt irough the Ventilating spaces.

In the machine as heretofore constructed, air from the air gap is circulated roperly through one part of the Ventilating uct, but

has been'sucked out of another part of the Ventilating duct, thereby causing eddies and a reverse iiow of air in the latter part of the ventilating duct. The part. of the duct out of which air is sucked is located between a slot and a space block, and is that part of the duct firstto be passed by a pole. The part of the duct through which air circulates properly is located between a space block and a slot, and is that part of a Ventilating duct which is last to be passed by a pole. have found by actual tests on certain dynamo electric machines, that the application of my invention thereto so smoothed out the flow of air, that 3() to 50 per cent more air flowed through the Ventilating ducts than throughlthe same machine without my invention, and that my invention substantially eliminated the whirls or eddies, pocket-s, and reverse tlow of air usually encountered in machines as heretofore constructed.

I desire it to be understood that my invention is not limited to the particular construction shown and described, and l aim in the appended claims to cover all modifications which do not depart from the spirit and scope of my invention.

, What I claim as new and desire to secure by Letters Patent of the United States, is:

l. lin a dynamo electric machine, two relatively movable members, one of said members being provided with slots and a` ventilating space, a wedge in the top of each of a plurality of said slots, each of said wedges having its external surface in the ventilating space angularly disposed with reference to the periphery of t-lie member having said slots, saidv surface extending substantially across the width of the slot, whereby the circulation through said Ventilating space is improved.

2. In a dynamo electric machine, two relatively movable members, one of said membeis being provided with slots and a ventilating space, a wedge in the top of each of a plurality of said slots, each of said wedges having its external surface in the Ventilating space angularly disposed with reference to the periphery of the member having said slots, whereb said wedge has a substantially triangular cross section in said Ventilating space, the narrow part of the triangle extending in the direction of the relative movement of said members, whereby the circulation through said Ventilating space is improved.

3. In a dynamo electric machine, two relatively movable members, one of said mem'- bers being provided with slots and a ventilating space, a wedge in the top of each of a plurality of said slots, each of said wedges having a surface in the Ventilating space extending substantially in line with the side et the slot and its external surface in the Ventilating space angulerly disposed with reference to the periphery ofi the member having said slots. said latter surface extending substantially across the width of theslot, whereby said wedge has a substantially triangular cross section in said Ventilating space and the circulation through said ventilating space is improved.

4. In a dynamo electric machine, two relatively movable members, one of said-members being provided with slots anda venti- I lating space, a wedge in the top or each of a plurality of said slots, each of said wedges having a sur-face in the ventilating space extending substantially in line with the side of the slot and its external surface in said ventilating space angularly disposed with reference to the periphery of the member having said slots, whereby said wedge has a substantially triangular cross section in said Ventilating space. the narrow part of the triangle extending in the ldirection of the relative movement ot said members, whereby the circulation through said Ventilating space is improved.

5. ln a dynamo electric machine, a rota.- table member, a stationary member provided with slots and a Ventilating space, a wedge in the top of each of a plurality of said slots, each of said wedges having its external surtace in the Ventilating space angularly disposed with reference to the periphery of the stationary member, said surface extending substantially across the width of the slot, whereby the circulation through said Ventilating space is improved.

6. A dynamo electric machine, a stationary member, a rotatable member provided with slots and a Ventilating space, a wedge in the top of each of a plurality of said slots, each of said wedges having its external surface in the. Ventilating space angularly disposed with reference to the periphery of said stationary member, whereby said wedge has a substantially triangular cross section in said Ventilating space, the narrow part of the triangle extending in the direction of rotation of said rotatable member. whereby' the circulation through said Ventilating space is improved.y

7. In a dynamo electric machine, a rotatable member, a stationary member provided with slots and a ventilat-ing space, a wedge in the top of each of al plurality of said slots.` eachof said wedges having asurface in the Ventilating space extending substantially in line with the side of the slot and its external surface in the Ventilating space angularlv disposed with reference to the periphery of said stationary member, said surface extending substantially across the width of the slot. whereby said wedge has a substantially triangular cross section in said Ventilating space and the circulation through the Ventilating space is improved.

8. In a dynamo electric machine, a rota- .s

table member, a stationary member provided with slots and a Ventilating space, a wedge in the top of each of a plurality of said slots, each of said wedges having a surface in the Ventilating space extending substantially in line with the side of the slot and its external surface in the Ventilating space angularly disposed with referenceto the riphery of said stationary member, whereby said wedge has a substantially triangular cross section in said Ventilating space,the narrow part of the triangle extending in the direction of rotation of vthe rotatable member, whereby the circulation through the ventilating space is improved.

9. In a dynamo electric machine, a rotatable member, a stationar member 'provided with slots and a venti ating space, space blocks in said Ventilating space having their tips curved away from the direction of rotation of said rotatable member, a wedge in the top of each of a plurality of said slots, each of said wedges having its external surface in the Ventilating space angularly disposed with reference to the periphery of the stationary member, said surface extending substantially across the width of the slot, whereby the circulation through the Ventilating space is improved.

y10. In a dynamo electric machine, a rotatable member, a stationary member provided with slots and a Ventilating space, space blocks in said Ventilating space having their tips curved away from the direction of rotation of said rotatable member, a wedge in the top lof each of a plurality of said slots, each of said wedges having its external surface in the Ventilating space angularly disposed with reference to the periphery of said stationary member, whereby said wedge has a substantially triangular cross section in said Ventilating space, the narrow part of the triangle extending in the direction of rotation of said rotatable member, whereby the circulation through the Ventilating space is improved.

11. In a dynamo electric machine, a rotatable member, a stationary member provided with slots and a Ventilating space, space blocks in tilating space angularly disposed with reference to the peri hery of the stationary member, said sur acel extending across the width of the slot, whereby said wedge has a substantiallytriangular cross section in said Ventilating space, and the said ventilat' mg space having their tips curved away substantially circulation through said Ventilating space is improved.

12. In a dynamo electric machine, a rotatable member, a stationary member provided with slots and a Ventilating space, s ace blocks in said Ventilating space having t eir tips curved away from the direction of rotation of said rotatable member, a Wedge in the top of each of a plurality of said slots, each of said wedges having a surface in the Ventilating space extending ysubstantially in line with the side of the slot and its external surface in the Ventilating space angularly disposed with reference to the periphery of said stationary member, whereby said wedge has a substantially triangular cross section in said Ventilating space, the narrow part of the triangle extending in the direction of rotation of the rotatable member, whereby the circulation through said Ventilating space is improved.

13. -In a dynamo electric machine, two relatively movable members, one of said members being provided with slots and a Ventilating space, a wedge in the top of each of a plurality of said slots, each of said wedges being cut away at the trailing tip to reduce eddies and improve -the circula-l tion through said Ventilating space.

14. In a 'dynamo electric machine, two relatively movable members, one of said members being provided with slots and a Ventilating space, a wedge in the top of each of a plurality of said slots, each of said Wedges being cut away at the leading tip so as to have a surface extending substantially in line with the side of the slot, and being cut away at the trailing tip so as to reduce eddies and improve the circulation through Said Ventilatlng space. I

l5. In a dynamo electric machine, a rotaltable member, a stationary member provided with slots and a Ventilating space, a wedge in the top of each of a plurality of said slots, each of said wedges being cut away at the trailing ti to reduce eddies and to improve the circu ation through said Ventilating v space.

16. In a dynamo electric machine, a rotatable member, a stationary member provided with slots and a Ventilating space, a wedge inthe top of each of a plurality of saidslots, each of said wedges being cut away at the leading tip so as to have a surface in the Ventilating space extending substantially in line with the side of the slot, and cut awayvat the trailing tip so as to reduce eddies and improve the circulation of air through Said Ventilating space.

In witness whereof, I have hereunto set my hand this Oct. 14, 1921.

VICTOR H. GREISSER. 

